This invention relates to a digital data searching apparatus for searching digital data satisfying a specified condition from a plurality of digital data to display a search result on a display device, and an image display apparatus.
In recent years, digital equipments such as digital cameras for obtaining an object image in the form of a digital image and measuring apparatuses for obtaining various kinds of digital data have come into wide use. Since the capacity of recording mediums such as HDD (hard disk drive) for storing digital data obtained by these digital equipments has been increased, a huge number of digital data can be stored in the same recording medium.
On the other hand, as the number of digital data stored in the recording medium increases, it becomes difficult to search a desired digital data. Thus, there has been a need for a digital data searching apparatus capable of efficiently searching desired digital data from those stored in the recording medium, and various proposals have been made to meet such a need.
For example, Japanese Unexamined Patent Publication No. 2001-228528 discloses an image administration method for classifying image data based on the date of photographing and the position of photographing. This method hierarchically classifies the image data by comparing at least one of differences between dates of photographing and differences between positions of photographing with a threshold value. The use of this image administration method enables realization of a digital data searching apparatus capable of searching digital data satisfying a specified condition with definite precision.
However, search by the photographing position data is difficult in the case of hierarchically classifying the image data by comparing the differences between the date data with the threshold value, whereas search by the photographing date data is difficult in the case of hierarchically classifying the image data by comparing the differences between the photographing position data with the threshold value. Thus, the image data satisfying the specified condition could not be efficiently searched from a plurality of image data.
Further, in the case of hierarchically classifying the image data by comparing both the difference between date data and the differences between the photographing position data with the threshold values, data at least one of the date data and the position data of which are similar are classified into the same group. For example, image data obtained by photographing during a tour in which participants travel in a wide area within a short period using a high-speed means of transportation such as an airplane may be classified into the same group even through they are obtained by photographing conducted at different places. In such a case, search by the photographing position data is difficult and the image data satisfying a specified condition cannot be efficiently searched from a plurality of image data. Such a problem occurs not only in the case of image data, but also in the case of other forms of digital data such as sound data and vibration wave data.